Couple pics of our new custom forged piston design:





You will notice that the crown is milled down to perfectly fit with the head and the quench pads squeeze the mixture into a tighter spot-which in turn speeds up the burn for increased power and efficiency. The marks you see are from the milling process and are actually completely smooth.

Also, since the combustion takes place away from the edges of the piston it should decrease the chances of damage to the edges & ringlands due to detonation.

Now they go off to PolyDyn for coating and then into my car with the Carrillo rods and APS TT kit

 

Sweet! Looks awesome!

 

Thanks Dave, can't wait to get it all put together and on the dyno for some tuning.

 

Those pistons are quite possibly the most beautiful I've ever seen! Nice work!

Do you have any pictures of the Carrillo rods?

Jeff

 

The price is pretty nice on them too

You can see pics of the rods here:

https://my350z.com/forum/showthread....threadid=96504

 

How much does the PolyDyn coating cost? I was actually looking into getting a coating for my pistons as well but I was unable to find anything decent. If you could provide some insight on the price range I would really appreciate it. Thanks.

 

As far as I know PolyDyn charges about $250 to do a ceramic "gold coat" top and moly coat the sideskirts. We can get you a better price if you are interested.

 

what's the dimple on the quench pad for? what c/r is this?

 

The dimple is to let the machinist know which direction the piston should be installed, i,e. dimple towards the front of the motor. This piston is an 8.5 c/r.

 

Whats the point of coating them??What does it do?

 

From the Swaintech website:

"When it came to improving automotive performance there was no free lunch. Everything engineers did to boost horsepower had a downside. Now, Swain Tech has developed a coating whose performance improvement doesn't come with a price. Swain GoldCoatä, a special thermal barrier coating for nitrous, turbo and blown engines, increases horsepower without sacrificing anything!
The energy that creates horsepower comes from the heat of combustion. Adding nitrous oxide to the fuel/air mix increases the intensity of the energy-generating heat in a combustion chamber. However, when that heat reaches a certain intensity it can melt pistons and other engine parts. GoldCoat protects pistons from heat damage and is actually extending engine life while boosting power.
GoldCoat is an extra high temperature ceramic coating, which can even withstand sudden bursts of heat like those a dragster generates during a nitrous, or nitro powered quarter mile. The ceramic, which gets its name from its gold color, is applied .003" thick to piston domes and cylinder heads. The coating holds heat inside the combustion chamber so more usable horsepower can be extracted from it by making the gaseous products of combustion expand more. The coating also protects the base aluminum by insulating it from intense, damaging combustion heat. Parts are protected from high temperature oxidation, and heat transfer is reduced by spreading the heat over the entire coated surface, encouraging proper flame travel, and eliminating hot spots and detonation. Less heat conduction through the pistons, wrist pins and rods keeps the crank and bearings cooler and oil temperature lower.
For even greater protection, Swain can coat piston skirts with Poly Molyä, a tungsten-molybdenum disulfide polymer matrix. Applied .0007" thick, this slippery coating works in conjunction with oil to provide an extremely low coefficent of friction, reduce piston scuffing and extend cylinder bore life.
Swain Tech Coatings are the original high performance, high technology coatings. The company's TBCä Thermal Barrier Coating has been used in all types of racing for more than 18 years."

 

I know you didn't ask me , but I have researched the topic.

There are typicaly two types of piston coatings applied:

a) Crown coating is a ceramic Thermal barrier coating (TBC).
This coating increases th eheat tolerance of the piston surface and reduces heating of the piston , which keeps more of the heat in the chamber were it belong and reduces the rate of piton expansion during warm-up.

b) Skirt coating is a Poly Moly (PM) suface bonded coating which provides durable dry lubrication between the skirt and bore. This reduces potential scuffing during cold start. Note Nissan uses a PM coating on the OEM pistons.

Note the two coatings work together to allow the bore to skirt clearance to reduced slightly , such that the rings seal better and
piston slap is reduced. It's money well spent IMO.

 

Those look exactly like the Custom Wiseco pistons they made us from the samples we sent them .

 

Could be, last I heard it was a design Wiseco made for Endyn's Honda applications. Wiseco suggested we try it on the Z32 and we did and then I recently asked them to make our 350 pistons with that design in addition to our skirt taper specs.

Have you heard how Dean made out when he went to court?

 

Beaautiful internals.

Good luck with everything.

Victor

 

How much does each piston weigh?
vs.
OEM

 

406 grams

I can't find the new stock 350 piston we have, maybe someone else knows the stock weight off hand.

 

I was just wondering why you chose PolyDyn over Swain Tech. I have just instructed my shop to send the block and parts to the machine shop but now am considering these coatings. Looks like PolyDyn is in Houston.

I just came back from a buisness trip up in Long Island and i just hope Swain Tech employees arent in a union.

 

AFAIK the coatings are basically the same thing and PolyDyn was recomended to us by the piston manufacturer.

 

If my memory is correct, the stock pistons are right around 424grams...give or take a few.

If someone knows where that info is the shop manual...I can dig it up.